The invention relates to a method for the removal of chlorate ions from solutions by the catalytic treatment at a noble metal catalyst in the presence of hydrogen.
It is known from WO 96/07617, that compounds of halogen and oxygen, which are formed as byproducts of the oxidative treatment of water and are contained in water in small concentrations, can be removed by the catalytic treatment at a noble metal catalyst in the presence of hydrogen.
Palladium on an oxide support is used as catalyst here, the porosity and abrasion resistance forming the criteria for selecting the support material.
The Japanese patent 63-514 describes a method for reducing the accumulation of chlorate ions in salt solutions of the chloralkali electrolysis, in that the circulating salt solution, in the presence of hydrogen, is passed over a catalyst layer.
Metals or metal oxides of the eighth subsidiary group of the periodic table of elements are used as catalyst.
Information concerning the effect of the support material on the catalytic effectiveness of the metals cannot be inferred from this publication.